* implemented PLC slice renewal
* restructured daemon code/startup
  - removed getfree daemon (replaced by plabdiscover; run from cron)
  - moved generic daemonizing code into libtestbed (class)
  - created plabrenewd - small script that utilizes daemonizing class
  - removed plabdaemon file.
  - updated bossnode startup scripts
* changed slice prefix - PLC denies permission w/ anything other than "utah"
* Minor semantic changes to module API to be more consistent with other parts.
* Some bug fixes.